Gun-sight and method of sighting



E. J. D. NEWITT.

GUN SIGHT AND METHOD or SIGHTING.

I APPLICATION FILED FEB. 4, 1919.

"1,326,464. Patented Dec. 30,1919.

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UNITED STATES PATENT OFFICE.

EDWARD J. n. nnwrrr, ornnw YORK, 1v. Y., ASSIGNOR or ONE-HALF T0 EARLE r. WATSON, or nor/1on1, NEW JERSEY.

GUN-SIGHT AND METHOD OF SIGHTIN'G.

Specification of Letters Patent.

Patented Dec. 30, 1919.

. lpplication filed February 4, 1919. Serial No. 274,867.

siding at New York, in the county and State of New York, have invented certain new and useful Improvements in Gun- Sights and Methods of Sighting, of which the following is a specification.

This invention relates to gun sights and has for one of its objects the provision of facilities for determining an elevation of the rearsight of a gun appropriate to the hitting of objects to which the distance 1s unknown or uncertain. V

Rear sights have been so constructed as to admit of adjustment in height relative to the axis of the gun to the end that the angle between the axisof the bore and the line of sight maybe increased or dimmlshed.

Marks are made upon the member carrying the essential element by which aim is taken, indicating the angle requisite to-compensate the fallof the bullet during the time taken to travel some such arbitrary distance as 100, 200, or 1000 yards, and the distances traveled in such time are normally engraved adjacent to such marks respectively.

With sights so constructed the criterion for the selection of the appropriate angle is distance, which implies a predetermination by measurement or. estimation of the dis tance; moreover the appropriateness of the angle selected'will depend upon the closeness ofthe estimated distance to the true distance.

In the drawings, Figure 1 is an elevation of a gun equipped with sights according to my invention;

Fig. 2 is an enlarged side elevation of the front sight; I r

Fig. 3 is a plan view of the rear sight;

Fig. 4: is a side elevation ofthe rear sight showing it folded down; v

Fig. 5 is a view of a modification showing provision for an adjustable zero setting, but

otherwise like 3, and

Figs. .6, 7 and 8 are diagrams that will bev referred to later. It will be understood that modifications of the disclosureherein Fig. 6 illustrates diagrammatically the relation of the angle of elevation of the rear- I sight to the gun, the line of aim, the trajectory, and the object when an angle of ele- LVatlOII appropriate to the distance has been selected.

2' a: is the line of sightto a point as on the object 0. t t a: is the trajectory or path of the projectile. i

It will Joe observed that the trajectory 25 t crosses the line of aim a short distance in front of the frontsight s and again intersects it at the point as finally reaching the ground 9 g at the point g if notstopped by the object.

This method involvesthe selection of such an-angle of elevation as shall cause the trajectory, line of sight and object to concur at the point an and it is obvious that the point as must in such case always lie very near the distant extremity of the trajectory.

When the selection of the angle of elevation is based upon an estimation of distance the latitude for error of estimation is equal to the distance the projectile advanceswhile its trajectory is falling a height equal to that of the objectand where the distance is long or the object has little vertical height the latitude is necessarily very small.

-It is well known that the trajectory resulting from any given angle of elevation is a constant as regards its height above-the line of sight at any given point in its length provided the angle of the line of sight to y jectory resulting from any given angle of elevation is a constant for any given rifle assuming that the cartridges have the same ballistic components.

- It is possible to predetermine the angles of elevation which will give trajectories of any desired height at their vertices or highest 4 points, and the lengths such trajectories respectively will attain.

In Fig. 7, there is shown diagrammatically a trajectory of which the vertex is a little less in height than an object 0 o o 0 0* shown at different points in its length. The line of aim i m m m 00 w intersects the object 0, o, 0 0 or 0 at its lower extremity and it will be observed that the trajectory intersects the object at some point throughout its entire length.

Thus it appears that it is possible to so:

a trajectory of which the vertex does not go higher than the height of an object. The criterion for such selection is generally known or easily estimated, namely the height of a familiar object in lieu of a generally unknown distance difficult of estimation. The velocity imparted to the projectiles by a modern rifle in such that the distances attained by trajectories of which the heights at the vertices do not exceed the heights of common objects is as great as it is desirable or necessary to shoot at such objects having regard to the effect of wind, inaccuracy and other causes which contribute to missing.

It is one object of my invention so to construct sights as to facilitate the use by the shooter of the principles stated heretofore.

To this end I predetermine the angles requisite to give trajectories of which the vertices respectively correspond approximately in height to the approximate height of many common objects. I then mark the heights of the said trajectories upon the sights and I may also mark the lengths of the said trajectories or distances attained adj acent thereto upon the sights.

The shooter may then select an angle of elevation which will give a trajectory not exceeding in height that of his object, and by aiming at its lower extremity the object will be within the path of the trajectory throughout the whole of its length.

Fig; 3 shows an example of construction in accordance with my invention, (1, a is the movable member engaging the ramps 0". The movable member a a slides upon the stationary members 0 c.

Fig. 4 shows the said stationary members 0 0 in side elevation. The figures 6, 12. and 18 indicate that if the upper edge of the slide is raised into contact with the engraved line immediately below each figure the re sulting trajectory imparted to the projectile on firing will attain the height at its vertex in inches expressed by the said figures on the member a respectively, and the length in yards expressed by the figures on the member 0 respectively.

Fig. 5 corresponds with Fig. 3 except thatthe scales 0 and 0 are made adjustable vertically so that if he so desires the user can shift them to change the Zero setting.

Further to explain the nature of my invention I direct attention to the diagram of Fig. 8. This illustrates an example of the use of my improved sight in conjunction with the principle of the selection of an angle of elevation of which the criterion for the selection is the vertical height of the object, the object being an ordinary deer, and the rifle being one having the ballistic capabilities of the U. S. Springfield rifle model 1903, an example in fact in which all the elements common in hunting are present.

The distance to the deer is unknown, and its vertical height has been the subject of a guess that it exceeds 12 inches, while it is actually 16 inches high and the hunter has elected to shoot with an angle of elevation which will give a trajectory 12 inches high at its vertex. The line L is the trajectory as it would appear if visible to the hunter when the rifle was fired and drawn to the same scale as the deer, and the point a: is the point of aim. The horizontal lines on the left indicate the heights of the ordinates of the trajectory at the distances the figures express in yards before the projectile has risen to its vertex and those on the right after it has passed its vertex and is falling. While primarily in hunting the object is the deer, the desire of the hunter is to place his projectile in the vital region surrounding the heart. It will be observed that in this case the deer would be hit in some part if at any distance from the rifle to 370 yards, and if standing at any distance between 50 and 350 yards from the rifle it would be struck in the vital heart region.

I claim l. The method of sighting a gun which consists in selecting the relative elevations of front and rear sights to give a trajectory whose vertex has a height above the sight line equal to the estimated vertical extent of the object, and then aiming at the lower part of the object, whereby the trajectory will intersect the object at whatever distance the latter may be within the length of such trajectory.

2. The method of operating a gun relatively to an object to be shot at, which consists in relatively adjusting the gun sights to give the axis of the gun an angle of elevation relatively to the line of sight, such that the maximum height of the trajectory above the line of sight is the same as the estimated vertical extent of the object, and then aiming at the lower part of the object, whereby the trajectory will intersect the object at whatever distance the latter may be within the length of such trajectory.

3. In combination, a gun, a front sight, at rear sight comprising a vertically adjustable member, and ascale for said rear sight, the divisions thereof being marked with the heights of the corresponding trajectories and positioned adjacent said vertically adjustable member.

4:. In combination, a gun, a front sight, a rear sight provided with a scale, the divisions thereof being marked with the heights of the trajectories, and means for alining any of said divisions with the front sight 1 5 along the line of sight.

5. In combination, a gun, a front sight, at rear sight comprising a vertically adjustable member, and a scale for said rear sight, the divisions thereof being marked with the 130 heights and the lengths of the correspondin trajectories and positioned adjacent said vertically adjustable member.

6. In combination, a gun, and a pair of sights therefor, comprising one sight having divisions graded according to the height of objects, said divisions beingpositioned with respect to the other sight so as to give corresponding trajectories bearing desired relation to the respective heights ofobjects and means for alining any of said divisions with the front sight along the line of sight.

7. In combination, a gun, and a pair of sights therefor, comprising one sight having one set of divisions graded according to the heights of objects, said divisions being positioned with respect to the other sight'so as to give corresponding trajectories bearing desired relation to the respective heights of objects, another set of divisions graded according to the distance of objects and means for alining any of said divisions With the front sight along the line of sight.

EDWARD J. D. NEWITT. 

